Abstract: There is provided a method for separating an arsenic mineral from a copper-bearing material containing arsenic, such as a copper ore or a copper concentrate, to obtain a copper concentrate with low arsenic grade. The method for separating an arsenic mineral from a copper-bearing material by flotation includes adding a flotation agent containing a depressant, a frother, and a collector to a slurry composed of a copper-bearing material containing arsenic, and blowing air into the slurry to float a copper concentrate, wherein the depressant is sodium thiosulfate. The sodium thiosulfate is preferably added in an amount of 10 kg or more and 200 kg or less in terms of sodium thiosulfate pentahydrate per ton of copper-bearing material to be subjected to flotation. Further, the oxidation-reduction potential of the slurry to be subjected to flotation, as measured against a silver/silver chloride reference electrode, is preferably ?10 mV or more and 50 mV or less.

Abstract: There is provided a method for separating an arsenic mineral from a copper-bearing material containing arsenic, such as a copper ore or a copper concentrate, to obtain a copper concentrate with low arsenic grade. The method for separating an arsenic mineral from a copper-bearing material by flotation includes adding a flotation agent containing a depressant, a frother, and a collector to a slurry composed of a copper-bearing material containing arsenic, and blowing air into the slurry to float a copper concentrate, wherein the depressant is sodium thiosulfate. The sodium thiosulfate is preferably added in an amount of 10 kg or more and 200 kg or less in terms of sodium thiosulfate pentahydrate per ton of copper-bearing material to be subjected to flotation. Further, the oxidation-reduction potential of the slurry to be subjected to flotation, as measured against a silver/silver chloride reference electrode, is preferably ?10 mV or more and 50 mV or less.

Abstract: The present invention concerns a method of separating variable ores containing copper, lead, zinc and the like as the refining material for non-ferrous metals and gangue minerals such as pyrite, quartz, feld spar and the like from dug out ores and, particularly, it relates to a flotation method. For obtaining non-ferrous metal valuable ores as concentrates from ores by a flotation method, flotation is conducted by using gaseous sulfurous acid or aqueous sulfurous acid as a depressant for controlling the floatability of pyrite. The flotation method comprises measuring the redox potential of an ore solution before and after the addition of gaseous sulfurous acid or aqueous sulfurous acid and determining an optimum addition amount by utilizing a proportional relationship present between the difference of the potential and the valuable quality enhancing rate.

Abstract: A method of beneficiation of complex sulfide ores comprises crushing and grinding complex sulfide ore containing sulfides of copper, zinc, iron and other minerals, subjecting the ground ores to differential flotation to obtain a bulk copper-zinc concentrate which is separate from pyrite and gangue, and passing the bulk copper-zinc concentrate through a high-gradient magnetic separator having an open-bore magnetic field filled with a matrix element, so as to recover separately a magnetic copper concentrate and a non-magnetic zinc concentrate. By combining the differential flotation with high-gradient magnetic separation, the present invention enables individual separation of copper and zinc concentrates without using many reagents in high volumes and by a simple process control.

Abstract: A method of treating effluents containing sulfur oxide ions, such as sulfite ions, thiosulfate ions, thionate ions and bisulfite ions, comprises blowing ozone-containing air into the effluent to reduce the COD level in the effluent to 6 mg/l or below, and neutralizing the so treated effluent with an alkali. This method is capable of producing neutral effluents with small equipment and within a short period of time, and the treated effluent will not experience an appreciable drop in the pH even if it is left to stand for a prolonged period.